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<html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8" /><title>Hyperlinked ECMA C# Language Specification</title><meta name="author" content="Jon Jagger" /><link rel="stylesheet" href="ecma334.css"></link></head><body><div align="right"><em><a href="http://www.jaggersoft.com">Jon Jagger</a></em></div><div align="right"><a href="mailto:jon@jaggersoft.com">jon@jaggersoft.com</a></div><form method="get" action="http://search.atomz.com/search/"><input size="30" name="sp-q"></input><input type="submit" value="Search C# Spec"></input><input type="hidden" name="sp-a" value="sp10024177"></input><input type="hidden" name="sp-f" value="ISO-8859-1"></input></form><a href="toc.htm">Table of Contents</a> <a href="1.htm">1</a> <a href="2.htm">2</a> <a href="3.htm">3</a> <a href="4.htm">4</a> <a href="5.htm">5</a> <a href="6.htm">6</a> <a href="7.htm">7</a> <a href="8.htm">8</a> <a href="9.htm">9</a> <a href="10.htm">10</a> <a href="11.htm">11</a> <a href="12.htm">12</a> <a href="13.htm">13</a> <a href="14.htm">14</a> <a href="15.htm">15</a> <a href="16.htm">16</a> <a href="17.htm">17</a> <a href="18.htm">18</a> <a href="19.htm">19</a> <a href="20.htm">20</a> <a href="21.htm">21</a> <a href="22.htm">22</a> <a href="23.htm">23</a> <a href="24.htm">24</a> <a href="25.htm">25</a> <a href="notes.htm">Notes</a> <a href="HyperlinkedCSharpECMA.zip">Download</a><span class="ruler"></span><span class="heading">ECMA-334 C# Language Specification</span><span class="navigate"><a href="9.4.4.3.htm"><img src="previous.gif" alt="previous" border="0" /></a><a href="9.4.4.5.htm"><img src="next.gif" alt="next" border="0" /></a></span><span class="clause-depth"><a href="8.htm"><img src="previous.gif" alt="previous at this level" border="0" /></a><a href="10.htm"><img src="next.gif" alt="next at this level" border="0" /></a> <span class="clause-number-link"><a href="9.htm">9</a></span><span class="clause-title-previous"> Lexical structure</span></span><span class="clause-depth"><a href="9.3.htm"><img src="previous.gif" alt="previous at this level" border="0" /></a><a href="9.5.htm"><img src="next.gif" alt="next at this level" border="0" /></a> <span class="clause-number-link"><a href="9.4.htm">9.4</a></span><span class="clause-title-previous"> Tokens</span></span><span class="clause-depth"><a href="9.4.3.htm"><img src="previous.gif" alt="previous at this level" border="0" /></a><a href="9.4.5.htm"><img src="next.gif" alt="next at this level" border="0" /></a> <span class="clause-number-link"><a href="9.4.4.htm">9.4.4</a></span><span class="clause-title-previous"> Literals</span></span><span class="clause-depth"><a href="9.4.4.3.htm"><img src="previous.gif" alt="previous at this level" border="0" /></a><a href="9.4.4.5.htm"><img src="next.gif" alt="next at this level" border="0" /></a> <span class="clause-number">9.4.4.4</span><span class="clause-title"> Character literals</span></span><span class="locator">
Paragraph 1</span><span class="paragraph"><span class="sentence"><span class="sentence-number">1</span> <a name="P1S1"></a>A character literal represents a single character, and usually consists of a character in quotes, as in 'a'.</span> <span class="grammar-production"><span class="name"><a name="character-literal"></a>character-literal</span> :: <span class="rhs"><span class="terminal">'</span> <span class="non-terminal"><a href="9.4.4.4.htm#character">character</a></span> <span class="terminal">'</span> </span></span><span class="grammar-production"><span class="name"><a name="character"></a>character</span> :: <span class="rhs"><span class="non-terminal"><a href="9.4.4.4.htm#single-character">single-character</a></span> </span><span class="rhs"><span class="non-terminal"><a href="9.4.4.4.htm#simple-escape-sequence">simple-escape-sequence</a></span> </span><span class="rhs"><span class="non-terminal"><a href="9.4.4.4.htm#hexadecimal-escape-sequence">hexadecimal-escape-sequence</a></span> </span><span class="rhs"><span class="non-terminal"><a href="9.4.1.htm#unicode-escape-sequence">unicode-escape-sequence</a></span> </span></span><span class="grammar-production"><span class="name"><a name="single-character"></a>single-character</span> :: <span class="rhs">Any character except ' (U+0027), \ (U+005C), and <span class="non-terminal"><a href="9.3.2.htm#new-line-character">new-line-character</a></span> </span></span><span class="grammar-production"><span class="name"><a name="simple-escape-sequence"></a>simple-escape-sequence</span> :: one of <span class="rhs"><span class="terminal">\'</span> <span class="terminal">\"</span> <span class="terminal">\\</span> <span class="terminal">\0</span> <span class="terminal">\a</span> <span class="terminal">\b</span> <span class="terminal">\f</span> <span class="terminal">\n</span> <span class="terminal">\r</span> <span class="terminal">\t</span> <span class="terminal">\v</span> </span></span><span class="grammar-production"><span class="name"><a name="hexadecimal-escape-sequence"></a>hexadecimal-escape-sequence</span> :: <span class="rhs"><span class="terminal">\x</span> <span class="non-terminal"><a href="9.4.4.2.htm#hex-digit">hex-digit</a></span> <span class="non-terminal"><a href="9.4.4.2.htm#hex-digit">hex-digit</a></span><sub>opt</sub> <span class="non-terminal"><a href="9.4.4.2.htm#hex-digit">hex-digit</a></span><sub>opt</sub> <span class="non-terminal"><a href="9.4.4.2.htm#hex-digit">hex-digit</a></span><sub>opt</sub> </span></span></span><span class="paragraph"><span class="note">[Note: A character that follows a backslash character (\) in a character must be one of the following characters: ', ", \, 0, a, b, f, n, r, t, u, U, x, v. Otherwise, a compile-time error occurs. end note]</span> </span><span class="locator">
Paragraph 2</span><span class="paragraph"><span class="sentence"><span class="sentence-number">1</span> <a name="P2S1"></a>A hexadecimal escape sequence represents a single Unicode character, with the value formed by the hexadecimal number following "\x".</span> </span><span class="locator">
Paragraph 3</span><span class="paragraph"><span class="sentence"><span class="sentence-number">1</span> <a name="P3S1"></a>If the value represented by a character literal is greater than U+FFFF, a compile-time error occurs.</span> </span><span class="locator">
Paragraph 4</span><span class="paragraph"><span class="sentence"><span class="sentence-number">1</span> <a name="P4S1"></a>A Unicode character escape sequence (<a href="9.4.1.htm">§9.4.1</a>) in a character literal must be in the range U+0000 to U+FFFF.</span> </span><span class="locator">
Paragraph 5</span><span class="paragraph"><span class="sentence"><span class="sentence-number">1</span> <a name="P5S1"></a>A simple escape sequence represents a Unicode character encoding, as described in the table below.</span>
<table border="1">
<tr>
<td><b>Escape</br>Sequence</b></td>
<td><b>Character</br>name</b></td>
<td><b>Unicode</br>encoding</b></td>
</tr>
<tr>
<td>\'</td>
<td>Single quote</td>
<td>0x0027</td>
</tr>
<tr>
<td>\"</td>
<td>Double quote</td>
<td>0x0022</td>
</tr>
<tr>
<td>\\</td>
<td>Backslash</td>
<td>0x005C</td>
</tr>
<tr>
<td>\0</td>
<td>Null</td>
<td>0x0000</td>
</tr>
<tr>
<td>\a</td>
<td>Alert</td>
<td>0x0007</td>
</tr>
<tr>
<td>\b</td>
<td>Backspace</td>
<td>0x0008</td>
</tr>
<tr>
<td>\f</td>
<td>Form feed</td>
<td>0x000C</td>
</tr>
<tr>
<td>\n</td>
<td>New line</td>
<td>0x000A</td>
</tr>
<tr>
<td>\r</td>
<td>Carriage return</td>
<td>0x000D</td>
</tr>
<tr>
<td>\t</td>
<td>Horiizontal tab</td>
<td>0x0009</td>
</tr>
<tr>
<td>\v</td>
<td>Vertical quote</td>
<td>0x000B</td>
</tr>
</table>
</span><span class="locator">
Paragraph 6</span><span class="paragraph"><span class="sentence"><span class="sentence-number">1</span> <a name="P6S1"></a>The type of a <span class="non-terminal"><a href="9.4.4.4.htm#character-literal">character-literal</a></span> is <span class="keyword">char</span>.</span> </span><span class="ruler"></span><table><tr><td><table align="left" bgcolor="navy"><tr bgcolor="navy"><td><font face="Arial,sans-serif" size="6" color="yellow"><strong>{ JSL }</strong></font></td></tr></table></td></tr><tr><td><font face="Arial,sans-serif" size="2" color="navy"><strong>Jagger Software Ltd</strong></font></td></tr><tr><td><font face="Arial,sans-serif" size="2" color="navy"><strong>Company # 4070126</strong></font></td></tr><tr><td><font face="Arial,sans-serif" size="2" color="navy"><strong>VAT # 762 5213 42</strong></font></td></tr></table><img src="valid-html401.png" align="left" height="31" width="88" alt="Valid HTML 4.01" /><img src="vcss.gif" align="left" height="31" width="88" alt="Valid CSS" /></body></html>⌨️ 快捷键说明
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